The Acid-catalyzed Reaction of Isocyanide with Oxetane
作者:Takeo Saegusa、Naotake Taka-ishi、Yoshihiko Ito
DOI:10.1246/bcsj.44.2473
日期:1971.9
The reaction of isocyanide with oxetane in the presence of BF3·OEt2 was studied; in this reaction a 1:1 cyclic adduct, 2-iminotetrahydrofuran, was formed. From 2-methyloxetane, 2-imino-5-methyltetrahydrofuran was exclusively formed. These findings suggest an SN2 mechanism for the cleavage of the oxetane ring. Oxetanes with electron-withdrawing substituents gave γ-alkoxybutyronitrile as the main product
SYNTHESIS OF ENERGETIC THERMOPLASTIC ELASTOMERS CONTAINING BOTH POLYOXIRANE AND POLYOXETANE BLOCKS
申请人:Sanderson Andrew J.
公开号:US20090088506A1
公开(公告)日:2009-04-02
This thermoplastic elastomer is present in a substantially solid state suitable for use as a binder for a propellant, explosive, and/or gas generant of a supplemental restraint system. The thermoplastic elastomer is formed from a composition including A blocks which are crystalline at temperatures below about 75° C. and B blocks which are amorphous at temperatures above about −20° C. The A blocks are derived from oxetane derivatives and the B blocks are derived from oxiranes and derivatives thereof. The A blocks and B blocks are end-capped with a diisocyanate having a first isocyanate moiety that is substantially more reactive with the terminal groups of the blocks than the second isocyanate moiety, whereby the more reactive first isocyanate moiety is capable of reacting with the terminal groups of the blocks, leaving the less reactive second isocyanate moiety free and unreacted. The end-capped A blocks and the end-capped B blocks are linked together with a linking compound having two isocyanate-reactive groups which are sufficiently unhindered to react with the free and unreacted isocyanate moieties of the end-capped polymers.
Method of producing thermoplastic elastomers having alternate crystalline structure for use as binders in high-energy compositions
申请人:THIOKOL CORPORATION
公开号:EP0335499A2
公开(公告)日:1989-10-04
A method is provided for synthesizing block polymers which are thermoplastic elastomers. The thermoplastic elastomers are useful as binders in high-energy compositions, such as propellants, explosives, gasifiers or the like. The block polymers have both (A) and (B) blocks; the A blocks being crystalline at temperatures below 60°C and the B blocks being amorphous at temperatures above -20°C. Both the A and B blocks are polyethers formed from monomers of oxetanes and/or tetrahydrofuran.
To prepare the block polymers, the (A) and (B) blocks are separately prepared and separately end-capped by reacting each block with a diisocyanate in which one of the isocyanate moieties is substantially more reactive with the terminal hydroxyl groups of the blocks than the other. Reaction of the more reactive isocyanate moiety with the terminal hydroxyl groups leaves the other isocyanate group free. The end-capped (A) and (B) blocks are mixed and reacted with a short linking compound which has two isocyanate-reactive groups.
LOVA gun propellants are formed from a thermoplastic elastomer and particulates of high-energy oxidizers, e.g., RDX and HMX.
LOVA 喷枪推进剂由热塑性弹性体和高能氧化剂微粒(如 RDX 和 HMX)组成。
Tetrafunctional polyethers
申请人:THIOKOL CORPORATION
公开号:EP0531591A1
公开(公告)日:1993-03-17
Polymers are produced from 4 and 5 member cyclic ethers, which polymers have hydroxyl functionalities of 4. The cyclic ethers are polymerized with an acid catalyst and a tetraol initiator having the general formula: